CD34 and acute promyelocytic leukemia: It was only in tube 3—which contained the criteria markers (CD117, CD34) used for creating the non-APL AML group—that the percentage of blasts in the hypergranular gate surpassed the cut-off value (Fig. 1); but even here, the pattern of the blasts within the gate differed from what we detected in the APL AML group: the blasts were not dispersed evenly throughout the gate but concentrated in its upper segment (Fig. 2, tube 3).